Image from Wyrmshadow
- Wachowski Prime - Text by M. Alan Kazlev
Matrioshka brain and original site of the Wachowski civilization.
- Wallace Dyson Swarm - Text by M. Alan Kazlev
Utopia Sphere dyson swarm, containing billions of vast habitats populated by sophont and subsophont/subsapient beings.
- Walloo and the Bellerophon Archipelago - Text by Steve Bowers
Pegasus Prefecture - Solar Dominion. Partially terraformed world abandoned after Version War
- Wasat - Text by Updated by The Astronomer and Dangerous Safety 2020
Central world of the House Conver Limis.
- Webistics - Text by M. Alan Kazlev
Important Communion of Worlds member-system, large stargate plexus outsystem.
- Wega - Text by Jorge Ditchkenberg
A paraterraformed moon in the Inner Sphere, famous Inner Sphere as a centre for independent thought and modosophont autonomy.
- Welsh - Text by M. Alan Kazlev
Chi Herculis I
- Whirlygig - Text by Mike Miller
Planet with high obliquity in the Inner Sphere.
- Whisper - Text by Todd Drashner
Planet covered in a sophont grassland xenoecology, perhaps of artificial origin.
- Wilson (zone) - Text by M. Alan Kazlev
Free Zone and home to diverse clades on the Dominion/MPA border, about 50 LY from Syrtis. Industries: tourism, contraband, bio- and nano-tech templates, mediacorp interests and associated virchtainments.
- Wilson Dyson Swarm - Text by M. Alan Kazlev
Utopia Sphere dyson swarm, consists of billions of habitats and biospheres, populated by sophont and subsophont/subsapient beings. A similar nearby dyson is called Wallace.
- Wolf 359 - Text by Anders Sandberg
Resource poor Inner Sphere system, in near proximity to Sol.
- World of Forking Paths, The - Text by Mark Ryherd
Gliese 33 supposedly the oldest continually inhabited paygeesu virch in the Terragen Sphere.
- World of Meditating Idols - Text by M. Alan Kazlev
Sagrei c - first planet to be discovered with alien ruins (20th century AT).
- Wurm - Text by Steve Bowers
Palaeolithic Metasoft baseline preserve world
- Xanthippe and Kate - Text by Steve Bowers
First worlds discovered with Thiogen lifeforms
- Xdim - Text by Anders Sandberg
Inner sphere system surrounding the M4V star HIP 38956.
- Xi Bootis B I - Text by Anders Sandberg
In 6222 a Nimbus colony was set up on Xi Bootis B I, but it persisted only for 400 years before dissipating.
- Xil - Text by M. Alan Kazlev
Extensive orbital habitat complex located at the Xi Bootis binary Lagrange points.
Text by Orion's Arm Editors
Initially published on 31 December 2007.